 
package com.mobi.Survey.charts;


import android.graphics.RectF;
import android.view.MotionEvent;

/**
 * The main handler of the touch events.
 */
public class TouchHandler implements ITouchHandler {
	  /** The chart renderer. */
	  private DefaultRenderer mRenderer;
	  /** The old x coordinate. */
	  private float oldX;
	  /** The old y coordinate. */
	  private float oldY;
	  /** The old x2 coordinate. */
	  private float oldX2;
	  /** The old y2 coordinate. */
	  private float oldY2;
	  /** The zoom buttons rectangle. */
	  private RectF zoomR = new RectF();
	  /** The pan tool. */
	  private Pan mPan;
	  /** The zoom for the pinch gesture. */
	  private Zoom mPinchZoom;
	  /** The graphical view. */
	  private GraphicalView graphicalView;

	  /**
	   * Creates a new graphical view.
	   * 
	   * @param view the graphical view
	   * @param chart the chart to be drawn
	   */
	  public TouchHandler(GraphicalView view, AbstractChart chart) {
	    graphicalView = view;
	    zoomR = graphicalView.getZoomRectangle();
	    if (chart instanceof XYChart) {
	      mRenderer = ((XYChart) chart).getRenderer();
	    }
	    if (mRenderer.isPanEnabled()) {
	      mPan = new Pan(chart);
	    }
	    if (mRenderer.isZoomEnabled()) {
	      mPinchZoom = new Zoom(chart, true, 1);
	    }
	  }

	  /**
	   * Handles the touch event.
	   * 
	   * @param event the touch event
	   */
	  public boolean handleTouch(MotionEvent event) {
	    int action = event.getAction();
	    if (mRenderer != null && action == MotionEvent.ACTION_MOVE) {
	      if (oldX >= 0 || oldY >= 0) {
	        float newX = event.getX(0);
	        float newY = event.getY(0);
	        if (event.getPointerCount() > 1 && (oldX2 >= 0 || oldY2 >= 0) && mRenderer.isZoomEnabled()) {
	          float newX2 = event.getX(1);
	          float newY2 = event.getY(1);
	          float newDeltaX = Math.abs(newX - newX2);
	          float newDeltaY = Math.abs(newY - newY2);
	          float oldDeltaX = Math.abs(oldX - oldX2);
	          float oldDeltaY = Math.abs(oldY - oldY2);
	          float zoomRate = 1;

	          float tan1 = Math.abs(newY - oldY) / Math.abs(newX - oldX);
	          float tan2 = Math.abs(newY2 - oldY2) / Math.abs(newX2 - oldX2);
	          if (tan1 <= 0.25 && tan2 <= 0.25) {
	            // horizontal pinch zoom, |deltaY| / |deltaX| is [0 ~ 0.25], 0.25 is
	            // the approximate value of tan(PI / 12)
	            zoomRate = newDeltaX / oldDeltaX;
	            applyZoom(zoomRate, Zoom.ZOOM_AXIS_X);
	          } else if (tan1 >= 3.73 && tan2 >= 3.73) {
	            // pinch zoom vertically, |deltaY| / |deltaX| is [3.73 ~ infinity],
	            // 3.732 is the approximate value of tan(PI / 2 - PI / 12)
	            zoomRate = newDeltaY / oldDeltaY;
	            applyZoom(zoomRate, Zoom.ZOOM_AXIS_Y);
	          } else {
	            // pinch zoom diagonally
	            if (Math.abs(newX - oldX) >= Math.abs(newY - oldY)) {
	              zoomRate = newDeltaX / oldDeltaX;
	            } else {
	              zoomRate = newDeltaY / oldDeltaY;
	            }
	            applyZoom(zoomRate, Zoom.ZOOM_AXIS_XY);
	          }
	          oldX2 = newX2;
	          oldY2 = newY2;
	        } else if (mRenderer.isPanEnabled()) {
	          mPan.apply(oldX, oldY, newX, newY);
	          oldX2 = 0;
	          oldY2 = 0;
	        }
	        oldX = newX;
	        oldY = newY;
	        graphicalView.repaint();
	        return true;
	      }
	    } else if (action == MotionEvent.ACTION_DOWN) {
	      oldX = event.getX(0);
	      oldY = event.getY(0);
	      if (mRenderer != null && mRenderer.isZoomEnabled() && zoomR.contains(oldX, oldY)) {
	        if (oldX < zoomR.left + zoomR.width() / 3) {
	          graphicalView.zoomIn();
	        } else if (oldX < zoomR.left + zoomR.width() * 2 / 3) {
	          graphicalView.zoomOut();
	        } else {
	          graphicalView.zoomReset();
	        }
	        return true;
	      }
	    } else if (action == MotionEvent.ACTION_UP || action == MotionEvent.ACTION_POINTER_UP) {
	      oldX = 0;
	      oldY = 0;
	      oldX2 = 0;
	      oldY2 = 0;
	      if (action == MotionEvent.ACTION_POINTER_UP) {
	        oldX = -1;
	        oldY = -1;
	      }
	    }
	    return !mRenderer.isClickEnabled();
	  }

	  private void applyZoom(float zoomRate, int axis) {
	    if (zoomRate > 0.9 && zoomRate < 1.1) {
	      mPinchZoom.setZoomRate(zoomRate);
	      mPinchZoom.apply(axis);
	    }
	  }

	  /**
	   * Adds a new zoom listener.
	   * 
	   * @param listener zoom listener
	   */
	  public void addZoomListener(ZoomListener listener) {
	    if (mPinchZoom != null) {
	      mPinchZoom.addZoomListener(listener);
	    }
	  }

	  /**
	   * Removes a zoom listener.
	   * 
	   * @param listener zoom listener
	   */
	  public void removeZoomListener(ZoomListener listener) {
	    if (mPinchZoom != null) {
	      mPinchZoom.removeZoomListener(listener);
	    }
	  }

	  /**
	   * Adds a new pan listener.
	   * 
	   * @param listener pan listener
	   */
	  public void addPanListener(PanListener listener) {
	    if (mPan != null) {
	      mPan.addPanListener(listener);
	    }
	  }

	  /**
	   * Removes a pan listener.
	   * 
	   * @param listener pan listener
	   */
	  public void removePanListener(PanListener listener) {
	    if (mPan != null) {
	      mPan.removePanListener(listener);
	    }
	  }
}